Fuel Economy Converter
Seamlessly convert between MPG and L/100km with our interactive efficiency tracking tool.
Miles per Gallon
Liters per 100 Kilometers
Efficiency Analysis
EXCELLENT
Based on standard passenger vehicle averages
E ————— F
British vs US MPG
Note: An Imperial (UK) Gallon is larger than a US Gallon. multiply US MPG by 1.2 for the approximate UK equivalent.
Standard Conversion
L/100km and MPG have an inverse relationship. As MPG goes up, L/100km goes down. 235.215 / MPG = L/100km.
Understanding Efficiency Metrics
- Enter your US MPG in the left input to get the Metric equivalent.
- Enter L/100km in the right input to calculate the US MPG.
- Observe the Visual Gauge to see your vehicle's efficiency rating (Excellent, Moderate, or High).
- Review the Comparison Info for tips on British vs. US measurements.
Frequently Asked Questions
How do I convert MPG to L/100km?
To convert US MPG to Liters per 100km, divide 235.215 by the MPG value. For example, 30 MPG becomes 7.84 L/100km.
Is a higher L/100km better?
No. Unlike MPG where higher is better, for L/100km, a lower number is better because it represents using fewer liters of fuel to travel the same 100km distance.
What is an excellent fuel economy?
Generally, for standard passenger vehicles, anything below 6.0 L/100km (39+ MPG) is considered excellent. Heavy SUVs often range from 12-15 L/100km (15-20 MPG).
Are British MPG and US MPG the same?
No. An Imperial (UK) Gallon is 4.54 liters, while a US Gallon is 3.78 liters. This means a car rated at 30 MPG (UK) would only be about 25 MPG (US).
Efficiency Highlights
- Instant bi-directional conversion
- Visual efficiency rating gauge
- Supports both US and Metric formats
- Accurate to 2 decimal places
- 100% private — your car stats stay local
- Mobile-optimized for clear comparison
Privacy-First Architecture
100% Local Processing
Unlike traditional online tools, Fuel Economy Converter processes your data entirely within your browser. Your files, numbers, and private info never reach our servers, ensuring absolute confidentiality.
Lightning Fast Speed
By eliminating the need for server uploads and downloads, we provide near-instant results. This technical approach saves bandwidth and provides a seamless user experience on both mobile and desktop.
Professional Grade Utility
The Fuel Economy Converter is part of the Toolkits Plus suite—a comprehensive collection of professional-grade utilities designed for modern digital workflows. Whether you're a student, professional, or hobbyist, our tools provide accurate, verified results without the clutter of traditional "thin" web applications.